Mesothelioma in Youth

Because mesothelioma typically develops decades after exposure to asbestos, the cancer is extremely rare in children and young adults. Only nine cases of the disease in young adults or kids were reported in the U.S. between 1999 and 2002.

Mesothelioma is a rare cancer most commonly diagnosed in people in their 60s and 70s, but doctors have reported some cases in young adults, children and even infants. In most cases of mesothelioma diagnosed in youth and childhood, there is no history of exposure to asbestos — the leading cause of the cancer.

During childhood, most exposures to asbestos come from the environment. However, it is unclear whether asbestos is a risk factor for cases diagnosed in childhood. Some studies suggest other potential causes, such as radiation exposure, the drug isoniazid and a history of mesothelioma in the family.

The symptoms of childhood mesothelioma are similar to the adult variety, and doctors use the same therapies to treat it. Symptoms in children typically include pleural effusion and acute episodes of pain, fever or shortness of breath. The leading treatment option first removes visible tumors with surgery, then uses chemotherapy or radiation to kill remaining cancer cells and prevent the cancer from returning.

Causes

Many cases of pediatric mesothelioma develop spontaneously, and while several risk factors have been identified, the majority of cases are not linked to asbestos or any one specific cause.

The primary cause of this cancer in adults – occupational exposure to asbestos – is not a risk for children. Kids may inhale or ingest environmental asbestos or experience secondhand exposure if a parent is exposed at work or somewhere else.

But the link between asbestos and pediatric cancer is weak. Researchers believe asbestos exposure during childhood may increase a person's risk for respiratory diseases later in life, but these early exposures hardly ever cause cancer in children or young adults.

It is rare for this age group to be diagnosed with an asbestos-related illness because it often takes several decades after the initial exposure to asbestos before conditions such as asbestosis and mesothelioma arise.

The occurrence of mesothelioma during infancy, childhood and adolescence supports the notion of true spontaneous mesotheliomas.

Joseph Tomashefski

Dail and Hammar's Pulmonary Pathology

Unlike adults, children diagnosed with mesothelioma rarely have a history of asbestos exposure. This has led researchers to look for other potential causes of the disease in children and young adults.

Fast Fact: A large study found that people first exposed to asbestos before age 10 were less likely to develop mesothelioma than those who were exposed to the fibers later in life.

One large international study involving 80 children diagnosed with mesothelioma reported a history of asbestos exposure in only two children, and two others met additional risk factors. The remaining 76 cases had no identifiable cause.

Some pediatric oncologists suggest radiation may play a role in the development of mesothelioma in children or young adults. Radiation exposure is only loosely linked to this cancer in adults. Patients who received radiation therapy during childhood for a disease called Wilms' tumor may face the highest risk for radiation-related mesothelioma, but this risk is still low. As of 1988, only one child and three adults were diagnosed with mesothelioma directly related to childhood radiation therapy for Wilms' tumor.

In utero exposure (exposure in the womb) to a drug called isoniazid has also been suggested as a risk factor for childhood mesothelioma. Pregnant animals injected with isoniazid have given birth to offspring with pulmonary tumors. However, only one recorded case of childhood mesothelioma in humans has resulted from isoniazid exposure.

Because of the insubstantial links among asbestos, radiation, isoniazid and pediatric mesothelioma, researchers believe children may develop the disease simply through genetic predisposition. Children born with certain genetic mutations may be more likely to have a cancerous response to non-asbestos fibers such as erionite.

In 2013, Dr. Michele Carbone and colleagues published a groundbreaking study on BAP1, a gene that plays an important role in cancer development. Carbone’s team determined that a mutation in the BAP1 gene can increase a person’s risk of developing mesothelioma, melanoma of the eye and other cancers.

The mutated BAP1 gene, which can be passed from parent to child, makes a person more likely to develop mesothelioma after exposure to asbestos and other environmental carcinogens.

What Are the Symptoms?

Children who develop this cancer often show the same symptoms as adults with the disease. Some of the primary symptoms include pleural effusions (excess fluid in the lungs), loss of appetite, abdominal pain and weight loss. Other possible symptoms include breathing problems, fever and fatigue.

Because many of these symptoms arise from diseases far more common than mesothelioma, doctors may not immediately suspect the cancer. Sometimes people with mesothelioma are misdiagnosed with common conditions like pneumonia, asthma or irritable bowel syndrome before test results confirm the correct diagnosis. Doctors may also mistake mesothelioma for other cancers with similar clinical features such as adenocarcinoma.

Cancer that spreads to distant locations, such as the brain, also occurs. One study noted this pattern in four of seven pediatric patients seen. Children may develop these symptoms more quickly than adults do, which reinforces one theory that pediatric mesothelioma may arise spontaneously.

How Is It Treated?

Children can receive many of the same types of treatments as adults. Debulking surgeries and chemotherapy are commonly used to manage pediatric mesothelioma.

The chemotherapy drugs given to adult patients are also used for children. Often, cisplatin is combined with either pemetrexed or gemcitabine. These drugs are administered over four to six cycles. Children receive these drugs on a dosing schedule that takes their weight and body size into consideration. One study found three out of four pediatric mesothelioma patients on a chemotherapy regimen survived at least 40 months after treatment.

Young Adults Who Developed Mesothelioma

One young adult who developed mesothelioma was Austin Lacy, who lost his battle at age 18. It is a mystery if he came in contact with asbestos.

Potential Sources of Childhood Exposure to Asbestos

Secondhand exposure from a parent who worked with asbestos

Asbestos in schools

Environmental asbestos (breathing the air or playing in/eating contaminated soil)

Asbestos in toys such as chalk, crayons and modeling clay

Adam Sager died of mesothelioma at age 25, years after documented asbestos exposure. When Adam was a toddler, he played in his home while his parents were making renovations. The home was built when asbestos was commonly used in insulation, and the home tested positive for asbestos.

Kevin Morrison was diagnosed with peritoneal mesothelioma in 2011 at age 21. He was treated at the Dana-Farber Cancer Institute, but lost his battle just a few months after being diagnosed. It is unclear if he came in contact with asbestos.